如何用JMeter发送HTTP请求创建用户？参数缺失问题排查

我使用JMeter通过HTTP请求调用后端控制器的create函数，批量创建5个数据相同的新用户。JMeter查看结果树返回响应：

"Missing mandatory params: Ref{val=[username, firstname, email, password, phonenumber, address]}"

请求已到达目标函数，但后端日志仅显示POST /user/create，无法看到传递的参数，且后端日志中所有参数提取结果（maybeUsername、maybeFirstname等）均为空值，需排查该问题。

后端控制器create函数代码 #

public Result create(Http.Request request){
    var body = safeJsonBody(request);
    var mandatory_params = Ref.of(List.of("username", "firstname", "email", "password", "phonenumber", "address"));
    var maybeUsername = extractNonEmptyString(body, "username");
    var maybeFirstname = extractNonEmptyString(body, "firstname");
    var maybeEmail = extractEmail(body, "email");
    var maybePassword = extractNonEmptyString(body, "password");
    var hashedPassword = "";
    if(!maybePassword.isEmpty())
    {
        var hash = hashFactory.mkHash(maybePassword.get(), Registration);
        hashedPassword= hash.get().hash;
    }
    var maybePhonenumber = extractNonEmptyString(body, "phonenumber");
    var maybeAddress = extractNonEmptyString(body, "address");

    logger.warn("maybeUsername                           : " + maybeUsername);
    logger.warn("maybeFirstname                           : " + maybeFirstname);
    logger.warn("maybeEmail                           : " + maybeEmail);
    logger.warn("maybePassword                           : " + maybePassword);
    logger.warn("maybePhonenumber                           : " + maybePhonenumber);
    logger.warn("maybeAddress                               : "+maybeAddress);

    if ( maybeUsername.isEmpty() || maybeFirstname.isEmpty() || maybeEmail.isEmpty() || maybePassword.isEmpty()) {
        checkIfIsPresent(mandatory_params,maybeUsername,"username");
        checkIfIsPresent(mandatory_params,maybeFirstname,"firstname");
        checkIfIsPresent(mandatory_params,maybeEmail,"email");
        checkIfIsPresent(mandatory_params,maybePassword,"password");
        checkIfIsPresent(mandatory_params,maybePhonenumber,"phonenumber");
        checkIfIsPresent(mandatory_params,maybeAddress,"address");

        return badRequest("Missing mandatory params: " + mandatory_params);
    }


    var tx = usersModel.upsert(maybeUsername.get(),maybeFirstname.get(),
            maybeEmail.get(),hashedPassword,maybePhonenumber.get(),maybeAddress.get());
    if (tx.isEmpty()){
        logger.warn(tx.toString());
        return internalServerError(stc_map_to_json(Map.of("status","error","message", "The user could not be created or updated.")).get());
    }
    return ok(tx.get());
}

排查步骤 #

• 验证JMeter请求格式：后端通过safeJsonBody(request)解析JSON请求体，需确保JMeter配置正确：

  1. HTTP请求方法设置为POST
  2. 添加HTTP信息头管理器，设置Content-Type为application/json
  3. 在"Body Data"中填写合法的JSON参数，示例：

     {
         "username": "test_user",
         "firstname": "Test",
         "email": "test@demo.com",
         "password": "demo123",
         "phonenumber": "13900139000",
         "address": "Demo Address"
     }
     

  4. 若使用CSV参数化，确认变量引用（如${username}）在JSON中正确替换，且CSV文件路径、编码配置无误

• 检查后端JSON解析逻辑：确认safeJsonBody方法能正确处理请求体，比如：

  • 是否仅接受application/json类型的请求
  • 是否处理了请求体的编码问题（如UTF-8）
  • 是否存在解析异常被静默处理的情况，导致返回空的JSON对象

• 添加请求体日志：在create函数开头添加日志，打印原始请求体内容，直接验证JMeter发送的参数是否到达后端：

  logger.warn("Received request body: " + request.body().asString());
  

• 确认JMeter批量请求的有效性：查看JMeter查看结果树中每个请求的"Request"标签页，检查每个请求的请求体是否正确生成，避免因线程组配置错误导致参数未被传递

内容的提问来源于stack exchange，提问作者Rune